Bidirectional communication between the cortex and thalamus via a specific cross-frequency channel is linked to conscious states. In humans, mice, and rats, low-frequency waves (1–13 Hz) sent from either the cortex or thalamus are consistently encoded by the other region using high gamma waves (52–104 Hz). This cross-frequency communication is diminished during propofol-induced unconsciousness and generalized spike-and-wave seizures, but enhanced by the psychedelic 5-MeO-DMT. Numerical simulations and neural recordings suggest these changes are mediated by shifts in thalamocortical electrodynamics toward or away from edge-of-chaos criticality, offering a mathematical framework for disrupted information transfer during unconsciousness.
A structural approach to consciousness models qualia—the qualities of experience—by examining either the internal organization of parts within an experience or the external relations between experiences. Integrating these two perspectives is a key step toward understanding phenomenally unified global experience. This paper describes both types of structural models and their category-theoretic formalizations, then proposes a sheaf-theoretic framework that maps mereological parts of experience to empirical measures of their qualia. Applying the framework to visual space demonstrates a formal description of experience's structure and conditions for phenomenal unity. The approach supports an empirical research program linking local and global phenomenal qualities.